Tropical Depression 5 forms in Hurricane Alley; could become tropical storm later today

View full sizeTropical Depression 5 has formed in the mid-Atlantic and could strengthen into a tropical storm later today.

Tropical Depression 5 has formed in the tropical Atlantic east of the Windward Islands, according to the National Hurricane Center. At 4 p.m. , the center of Tropical Depression 5 was located near latitude 12.2 north, longitude 49.0 west. Some strengthening is forecast during the next 48 hours, and the depression could become a tropical storm tonight or on Thursday.

On the forecast track, the center of the tropical cyclone should be near the Windward Islands on Friday.

Forecasters decided to declare the low pressure system a tropical depression after satellite images showed its low-level circulation east of the Windward Islands had become better defined, according to a discussion message issued by Senior Hurricane Specialist Richard Pasch and Hurricane Specialist Eric Blake.

"Deep convection has pulsed a bit, and is somewhat lacking over the northern part of the circulation," the message said. "However, the system has now acquired sufficient organization to be classified as a tropical depression."

The forecasters warned that predicting changes in intensity for the new depression will be challenging. Wind shear created by a large upper level low pressure system north of the depression will affect its development during the next few days, and only slow strengthening is forecast.

Two favored predictive computer models are giving widely different forecasts for how the system will evolve as it moves over the Caribbean Sea at the end of the five-day forecast period, the message said, with one showing significant strengthening by the end of five days, and the other predicting it will revert to a tropical wave.

The forecasters said they are leaning toward the stronger storm prediction, for now.

The government of Barbados has issued a tropical storm watch for Barbados, St. Vincent and the Grenadines, and Dominica.

The government of St. Lucia has issued a tropical storm watch for St. Lucia. The government of France has issued a tropical storm watch for Martinique and Guadeloupe.